Respiratory pathophys Flashcards
Upper respiratory
above the larynx
pharyngitis, otitis media, sinusitis
Lower respiratory tract
below the larynx
acute bronchitis, chronic bronchitis, pneumonia, TB
Defense mechanisms against infections, URT
nasal hairs, gag reflex, epiglottis, mucosal lymphoid tissue, secretory immunoglobulins
Defense mechanisms against infection, LRT
secretory IGA, ciliated epithelium, bronchospasm, cough reflex, alveolar macrophages
Conditions that impair host defenses
Cigarette smoking
Intubation
Recurrent laryngeal nerve damage
Absent gag reflex
Cystic fibrosis
Congenital absence of IgA
Oversedation
Cigarette smoking
paralyzes cilia, destroys epithelium, decreases number of macrophages, decreases macrophages’ activity
Intubation
impairment of host defenses, bypasses upper respiratory tract
Recurrent laryngeal nerve damage
at risk during surgeries
speech, swallowing, coughing
Absent gag reflex
1/3 individuals don’t have it, increased risk for aspiration
Cystic fibrosis
overproduction of thick sputum, risk for increased infection
Congenital absence of IgA
increased risk for infection
Oversedation
decreases ability to cough
usually occurs was opiates or other CNS depressants
Pathogenesis of lower respiratory tract infections
- nasopharyngeal colonization with the organism and subsequent aspiration of nasopharyngeal secretions
- reflux of GI bacteria and aspiration of contents in presence of antacid use
Acute bronchitis
D: inflammation of bronchial mucosa and increased endobronchial mucus production, due to infection
E: viral and seasonal
CP: dry cough or cough with purulent or mucoid sputum. myalgias, sore throat
T: no antibiotics
Pneumonias
inflammation of lungs with consolidation (something in lungs besides air
can be bacterial (community, nosocomial, aspiration), viral, mycoplasma
Atelectasis
partial or complete collapse of lung
_____ can lead to aspiration pneumonia
dysphagia
Dysphagia
difficulty swallowing, can lead to aspiration pneumonia
How can we prevent aspiration?
NPO
Positioning, semiupright in bed with HOB >30 (semi-fowler and fowler’s)
Clinical Presentation of Bacterial pneumonia
abrupt onset of high fever
chills, cough with purulent sputum
chest pain, dyspnea, myalgias, malaise, tachycardia
altered mental status in elderly
Diagnosis and Treatment of Bacterial Pneumonia
DX: hx, physical exam, chest xray, blood cultures, sputum culture, WBC count
Treatment: ABX, bronchodilators, airway clearance techniques
Outcome of bacterial pneumonias
Good in young and middle-aged, little or no permanent defect
elderly can die, 30-50% in bacteremic pneumonia. Harder to diagnose
Clinical presentation & Diagnosis of Viral pneumonia
S/S: fever, dry cough, myalgias, tachypnea, flu-like symptoms, scattered crackles, hypoxemia
DX: History, PE, CXR
Treatment and Outcome Viral Pneumonias
Treatment: symptomatic, no ACTs
Outcome: usually resolvles w/out complications or lasting damage, mortality <5%.
Covid-19 is an example
Pleurisy
inflammation of pleural lining of the lung with exudate formation into pleural cavity (pleural effusion)
secondary to pneumonia
pleural infection w/TB or influenza
Secondary to other systemic illnesses
Pleurisy Clinical Presentation
Chest pain due to edema
referred to chest wall, abdomen, upper trap, shoulder
Cough, fever, tachypnea
Diagnosis and Treatment of Pleurisy
Dx: History & PE
pleural friction rub. splinting area of pain may decrease discomfort
Tx: time, NSAIDs, other analgesics
TB Etiology
acquired by inhalation of m. tuberculosis in aerosols & dusts
airborne transmission extremely efficient, droplets are sprayed by infectious individuals
thrives in crowding, poverty, poor nutrition
Primary Infection of TB
latent TB infection
-transient bacteremic phase brought under control by host immune system
-mild symptoms or asymptomatic
-lung lesion and enlarged lymph nodes walled off (granuloma)
Secondary active TB infection clinical presentation
TB disease, active TB
lapse in immune competence allows reactivation of dormant mycobacteria
any organ can be affected, lungs are the most due to high PO2
Dx and Tx of TB
DX = history, PE, CXR, sputum
Tx: anti-TB drug combo (isoniaxid, rifampin, ethambutol
Outcome and Prevention of TB
Outcome: modern cure rates are high. Development of multi-drug resistant TB (low compliance), TB is leading cause of people with HIV
Prevention: improved social conditions, immunizations, wear appropriate PPE
Tuberculosis Risk Factors
HIV
Diabetes
Substance abuse
Homelessness
Migrant workers
healthcare workers
jails
nursing homes
COPD
preventable and treatable disease
airflow limitation that is progressive
reaction to noxious particles or gases
chronic airflow limitation caused by mixture of small airway disease and parenchymal destruction
How does airflow obstruction occur in COPD?
Inflammation within airways
Mucus obstructs airways
Remodeling/scarring
airways collapse due to damaged parenchyma
How is COPD diagnosed?
S/S: shortness of breath, chronic cough, sputum
RF: host factors, tobacco, occupation, pollution
Spirometery: required to establish dx
other tests: CXR, ABGs, CBC/increased HcT
Clinical Features of COPD
40s to 50s with cough or acute chest illness
dyspnea on exertion
Hx of episodic wheezing and dyspnea
CXR: hyperinflated lungs, flat diaphragm, enlarged right ventricle
Risk factors for COPD
Environment
Host
Environment for COPD
Tobacco smoke
Occupational exposure
Indoor/outdoor air pollution
infections
poverty
Pack-year
1 pack per day x 40 years
2 packs per day x 20 years
Host and COPD
Genetic predisposition
specific gene abnormality (antitrupsin deficiency)
aging (increased
females
early lung development
____ is required to make a diagnosis of COPD
spirometry